Lead-acid batteries are commonly used in applications, such as in an automotive battery, in which adverse circumstances may result in the battery tipping from an intended orientation. Leakage of the battery in a tipped position can result in substantial damage including destruction of the battery itself, and consequently, acid constraining covers for lead-acid batteries are known in the art. Many covers comprise a lower and upper section that combine to form an enclosed area in communication with the acid inside the battery. When the battery is tipped ninety degrees onto a side, the acid flows into the enclosed area formed by the lower and upper sections, providing additional protection from the acid fully exiting the battery and cover assembly.
U.S. Pat. No. 5,843,593 issued to Fritts et al. (hereinafter “Fritts”) discloses such a combination of an intermediate cover 14 and an outer cover 16 attached to a lead-acid battery housing 12. The combination of the intermediate cover 14 and outer cover 16 creates a network of labyrinths 20 between cell vents 22 communicating with the acid inside the battery and an atmospheric vent 38 communicating with the exterior of the battery and cover assembly. Each cell vent 22 in the cover corresponds to a cell of the battery. The labyrinth of Fritts constrains acid exiting the battery cells through the cell vents 22 in multiple tipped orientations. The shape of the labyrinth in Fritts, however, permits acid from multiple cells to mix within the cover in certain orientations, such as when the battery is tipped ninety degrees onto side 168 shown in FIG. 11; the acid from three cells has mixed in passage 130b. When the acid from multiple cells connects, an electrical short is formed between the cells, reducing the cell voltage and the life of the battery.